Trade-in Valuator

Trade-in Valuator

> Caveat: this skill is one author's playbook + 5-scenario stress test. Verify state fees / CPO terms / EV credits / dealer practices against current sources before quoting numbers to a dealer or making financial decisions. Not tax, legal, or financial advice.

last_verified: 2026-05-18

Narrow-trigger skill: produce a defensible trade-in valuation, decide separate-sell vs trade-in, and stage lien-payoff timing. Defers full reference content to ../orchestrator/references/trade_in.md and state-specific tax mechanics to ../orchestrator/references/state_fees.md.

When to invoke

User says any of: "valuate my trade", "what's my Civic worth", "KBB vs private party", "trade-in tax credit", "lien payoff", or the CN triggers in the frontmatter. Skip this skill if there is no trade (Phase 1 trade gate = NO).

5-anchor valuation framework

Per ../orchestrator/references/trade_in.md Section 1: every trade vehicle has four book/market valuations -- and for EVs and PHEVs, a fifth anchor: battery State of Health (SoH). Capture every applicable anchor at Phase 1 -- misreading them is the #1 source of buyer loss in trade-in deals.

| # | Anchor | What it is | Typical relationship | Role | |---|---|---|---|---| | 1 | KBB Instant Cash Offer | Real cash a participating dealer will pay TODAY, no negotiation | Lowest of the four (dealer floor) | Walk-floor outside option. Any dealer trade offer below this is asking buyer to subsidize. | | 2 | KBB Trade-In Value (Fair condition mid) | KBB book trade-in value at stated condition | $600-$1,300 above KBB Instant Offer | Mid; fair dealer trade target. Use as primary anchor. | | 3 | KBB Private Party Value | What buyer can realistically sell for on Craigslist / FB Marketplace | $1,500-$3,000 above KBB Trade-In; transacts 7-14 days for clean 1-owner | Upper bound; the price the buyer trades convenience for. | | 4 | Wholesale (Manheim MMR / Black Book) | Dealer auction acquisition floor | Lowest; dealer-internal | Internal benchmark only; buyers rarely see MMR. Estimate ~5-10% below KBB Instant Offer for popular models. | | 5 | Battery State of Health (SoH) -- EV/PHEV only | Verified pack capacity retention (%) from OBD-II / dealer scan / mfr app -- NOT the dashboard range estimate | Cross-cutting modifier on anchors 1-4, not a standalone $ figure | The dominant EV factor: for a used EV the pack is the most expensive component, so SoH moves resale more than paint/trim/often mileage. Books usually ignore it -- so treat books as a soft ceiling and adjust for SoH. |

Also useful: NADA Trade-In Clean is often $300-$700 above KBB Trade-In on popular Hondas/Toyotas; treat as higher-of-two-books anchor when negotiating.

Anchor 5 -- battery SoH (EV/PHEV trades)

For any EV or PHEV trade, books (KBB/NADA/Black Book) systematically miss the battery: they often apply no SoH adjustment, lag fast EV price swings by months, and lump EVs onto an ICE depreciation curve. So anchors 1-4 are necessary but not sufficient -- layer SoH on top. Approximate market behavior (verify; no rigid formula -- dealers apply an invisible adjustment table):

| SoH band | Effect vs. a healthy peer (same model/age/miles) | |---|---| | 90-95%+ | Premium / supports book | | ~85-89% | Roughly book; minor or no deduct | | ~80-84% | Begins to discount | | § 25E is TERMINATED (2025-09-30) — and was always a separate transaction. > The federal Used Clean Vehicle Credit (IRC § 25E, formerly up to $4,000) was > terminated by OBBBA (Public Law 119-21) for any vehicle acquired after > 2025-09-30 — it is not available for a 2026 used-EV purchase and must NOT > be counted in OTD / net-price math. See the CRITICAL banner in ev-buyer-helper. > Separately (and even when it existed), § 25E attached to the buyer purchasing > a qualifying used EV, NOT to the EV being traded away — so it never offset a > trade valuation regardless. Historically its $25,000 price cap was measured > before trade-in value, so a big trade allowance did not slip a car under the > cap. Full mechanics + historical detail (price cap, MY≥2yr, dealer point-of-sale > transfer + IRS ECO reporting, MAGI caps, termination 2025-09-30) live in > ../orchestrator/references/ev_buyer_playbook.md § 25E and trade_in.md > Section 13e (HISTORICAL). Do not conflate the two, and do not present § 25E as a > live buy-side credit.

Capture-all-four checklist (12 fields)

Per trade_in.md, the prior 6-field placeholder is insufficient. At Phase 1 capture: (1) Year/make/model/trim, (2) Mileage, (3) Title status, (4) Lien holder + payoff balance, (5) Key count, (6) Cosmetic issues, (7) Mechanical issues, (8) KBB Instant Cash Offer + screenshot, (9) KBB Trade-In Value at stated condition, (10) KBB Private Party Value, (11) NADA Trade-In Clean, (12) Wholesale estimate (MMR or Black Book if available). EV/PHEV adds (13) verified battery SoH % + report source (OBD-II / dealer scan / mfr app) + report date, and (14) does the factory battery warranty transfer to the next owner? (Y/N + remaining term).

State trade-in tax credit matrix

Excerpt from ../orchestrator/references/state_fees.md. In states allowing trade credit, sales tax applies to NET (sale price minus trade allowance), not gross.

| Trade credit status | States | |---|---| | YES (full, uncapped) | NJ, NY, PA, TX, OH, NC, GA, WA, DC, MD, FL | | YES (capped first $10k) | IL | | YES (capped first $9k) | MI | | NO | CA, KY, VA | | N/A (no sales tax on vehicles) | OR, MT, NH, AK, DE |

Worked example -- NJ $25k sale + $10k trade:

• Tax base = $25,000 - $10,000 = $15,000
• NJ sales tax 6.625% on $15k = $993.75
• Without trade credit: 6.625% on $25,000 = $1,656.25
• Trade credit saves $662.50

Same deal in CA (no credit): tax base stays $25k, savings = $0. Move the trade to a separate private-party sale if the state-loss is large.

Separate-sell vs trade-in decision

Decision rule:

• Private-party premium = (KBB Private Party) - (Dealer Trade Allowance)
• Trade-credit value = (Trade Allowance) * (State combined tax rate, if credit)
• If private-party premium > trade-credit value + buyer's convenience price

($1,000-$3,000 typical), sell separately.

• Else trade in.

In NJ at 6.625% with a $15k trade allowance vs $17k private party: premium = $2,000; trade-credit value = $993; net cost of trading = $2,000 - $993 = $1,007. If buyer values convenience > $1,007, trade in; otherwise sell separately.

In CA same numbers: premium $2,000; trade-credit value $0. Sell separately almost always wins.

Lien payoff workflow

Per trade_in.md Section 4 (a-d):

| When | Step | Detail | |---|---|---| | T-7 days | Request 10-day payoff letter from lien holder | Letter states exact dollar amount valid through a date 10 days out. Some lien holders charge a $25 admin fee. | | T-3 days | Dealer cuts payoff check, overnights to lien holder | Clearance typically 5-10 business days. Get a copy of the check + tracking number from dealer F&I. | | T+0 (delivery) | Title transfer pending lien release | Dealer holds title work until lien release arrives. Buyer drives away on temp tag. | | T+14-30 | Lien release filed with state DMV | New title issued to dealer (or assigned to next buyer). Confirm release was filed; some lien holders are slow. |

If payoff balance > trade allowance (underwater trade): the difference is rolled into the new loan principal (cheapest financing) OR paid out of pocket. Disclose to dealer at Phase 1 -- hiding negative equity blows up Phase 9.

High-mileage trap

For vehicles over 100,000 miles:

• KBB Instant Cash Offer often returns "no offer" or unrealistically low.
• Private party is the realistic-only path; expect 14-30 days on market.
• If buyer cannot wait, accept dealer wholesale offer is essentially MMR.

Separate-the-negotiation 5-round protocol

NEVER let the dealer shell-game sale price against trade allowance.

1. Round 1: Agree the new-car OTD (no trade mentioned). Lock in writing.
2. Round 2: Introduce trade. Ask for dealer's blind trade offer.
3. Round 3: Compare dealer offer to KBB Instant Cash Offer (anchor #1). If

dealer offer Vehicle: Anchors: KBB-Instant $X / KBB-Trade $Y / KBB-Private $Z / NADA $N Battery (EV/PHEV only): SoH via on ; warranty transfers? ; SoH adj to book: Lien: $payoff balance, holder, 10-day letter on file? (Y/N) State: , trade credit: Tax savings if traded: $ Decision: TRADE-IN vs SEPARATE-SELL (with reasoning) Walk-floor: $ Negotiation target: $

Hand off to Phase 6 negotiation when traded; hand off to private-party listing
help when separate-sell.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [DaizeDong](https://github.com/DaizeDong)
- **Source:** [DaizeDong/buy-me-a-car](https://github.com/DaizeDong/buy-me-a-car)
- **License:** MIT

Install and usage instructions live in the source repository linked above.